BEIRUT - Air strikes on a camp in northwest Syria run by rebel fighters backed by Turkey killed at least 35 people and wounded scores on Monday, a war monitor and a rebel source said.
The rebel source said suspected Russian strikes targeted the Failaq al-Sham faction in their base close to the border with Turkey, killing 35 and injuring 50 others. Many remained missing, the source said.
There was no immediate comment from Moscow.
The UK-based Syrian Observatory for Human Rights put the death toll at 78, with scores wounded.
Syrian government forces, backed by Russian air power, have driven rebels back to a pocket of territory adjoining Turkey after more than nine years of conflict triggered by protests against President Bashar al-Assad in 2011.
Ankara sent thousands of troops into the region this year to stall the Syrian government advances and prevent an influx of refugees from the Idlib border region into Turkey.
Monday's air strikes targeted the camp near Kafr Takharim, about 10 km (6 miles) from the Turkish border in Syria's Idlib province, the rebel fighter said.